1. Technical Field
The present invention relates to a density measuring device, a liquid developer storing apparatus, and an image forming apparatus capable of measuring the density of liquid toner acquired from dispersing toner into a carrier liquid.
2. Related Art
A liquid density detecting method is known that detects the density of a liquid in a broad range. In the method, a liquid as a target for density measurement is filled in concave parts that are formed in multi-level parts between an eccentric disc part and two disc parts in the circumferential direction by using a liquid carrying roller formed by integrally forming the eccentric disc part and two disc parts that have a same diameter larger than that of the eccentric disc and have the eccentric disc part interposed there between. Then, the liquid is formed to have a plurality of film thicknesses different from each other corresponding to the multi-levels, and the density of the liquid is detected based on the output of an optical sensor for the plurality of the film thicknesses (see JP-A-2000-249653).
However, in JP-A-2000-249653, at least two shafts of the disc parts and the eccentric disc part are needed, and a large space is required. In addition, a gap in the circumference is detected, thus an electrical process cannot be easily performed. In addition, the developer needs to be pumped from a storage unit by using a pump or the like, the number of constituent components is increased. In addition, since the density of the pumped developer is detected, the density is not identical to that of the developer inside the storage unit.